Apply LOCAL_LDLIBS to target build rules too.

Use LOCAL_LDLIBS to link against prebuilt libraries (such as NDK
libraries).
Previously LOCAL_LDLIBS only applies to host modules and the behaviour
confuses users.

Change-Id: I515546d7b59ef54e8ef09050eb58ec63534c9291
diff --git a/core/combo/TARGET_linux-x86.mk b/core/combo/TARGET_linux-x86.mk
index 01f8242..4f66765 100644
--- a/core/combo/TARGET_linux-x86.mk
+++ b/core/combo/TARGET_linux-x86.mk
@@ -194,7 +194,8 @@
 	-o $@ \
 	$(PRIVATE_LDFLAGS) \
 	$(PRIVATE_TARGET_LIBGCC) \
-	$(if $(filter true,$(PRIVATE_NO_CRT)),,$(PRIVATE_TARGET_CRTEND_SO_O))
+	$(if $(filter true,$(PRIVATE_NO_CRT)),,$(PRIVATE_TARGET_CRTEND_SO_O)) \
+	$(PRIVATE_LDLIBS)
 endef
 
 define $(combo_2nd_arch_prefix)transform-o-to-executable-inner
@@ -219,7 +220,8 @@
 	-o $@ \
 	$(PRIVATE_LDFLAGS) \
 	$(PRIVATE_TARGET_LIBGCC) \
-	$(if $(filter true,$(PRIVATE_NO_CRT)),,$(PRIVATE_TARGET_CRTEND_O))
+	$(if $(filter true,$(PRIVATE_NO_CRT)),,$(PRIVATE_TARGET_CRTEND_O)) \
+	$(PRIVATE_LDLIBS)
 endef
 
 define $(combo_2nd_arch_prefix)transform-o-to-static-executable-inner